Compilare: main.cpp: In function 'void a(int)': main.cpp:12:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < mu[nod].size(); i++){ ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:45:11: warning: unused variable 'x' [-Wunused-variable] int t,x,y; ^ main.cpp:45:13: warning: unused variable 'y' [-Wunused-variable] int t,x,y; ^